Pilot trainer



June 20, 1944. w. H. HUTTER 2,352,101

PILOT TRAINER y Filed Aug, 7, 1942 2 sheets-sheet 2 i jtd, 3.

Patented June 20,l 1944 UNITED STATES PATENT OFFICIIE.l

PILOT TRAINER William` III. Hutter, Chicago, Ill. Application August '1,1942, serialize. 453,945

Claims.

when the airplane controls are manipulated, and 5 further in which thepilot appears to approach the earth while diving and in which it can bemade to appear that the pilot is iiying at difierent distances above theground.

1n the Lucien J. Beindorf Patent N o. assenso 1o dated December 7, 1943,a pilot trainer is shown and described in which a scene shifts aboutwhenthe airplane controls are manipulated so that the relative movementbetween vthe scene and the pilot is substantially the same as thesimilar rell5 ative movement in a conventional airplane while in iiight.The apparatus as disclosed in this prior patent, therefore, simulateschanges in attitude of the aircraft.

The primary object of the present invention is to provide an improvementin the device described in the before-mentioned patent so that inthedevice of the present invention the pilot obtains the 'impression ofmovement toward and away from the ground, as well as changes inattitude. Y

A further object of the present invention is to provide novel trainingapparatus in which an operator can, simulate approaches to landings.

Yet another object of the .present invention is to provide an improvedpilot trainerin which simulated dives and climbs appear more realistic.

Yet another object of the present invention is to provide a pilottrainer inwhich a scene is projected upon a screen and in which objectsin the` scene increase in size when the airplane controls aremanipulated in a manner that would place a conventional airplane in adiving or gliding attitude.

Still another object of the present invention is 4o to provide a deviceaccomplishing the above mentioned objectives at comparatively low cost-Yet another'object of the present invention is to provide a noveltraining device in which a scene is projected upon the screen and inwhich the scene has a third dimensional or relief eifect.

Other objects and advantages will become apparent from the followingdescription of a preferred embodiment of my invention.

In the accompanying drawings in which' similar 50 characters ofreference refer to similar parts throughout the several views'.

Fig. l. is a somewhat diagrammatic perspective View of operatingmechanism embodying the. present invention;

Fig. 2 is an electrical diagram yillustrating the V electrical mechanismembodied in the apparatus illustrated in Fig. 1; and

Fig. 3 is aside elevation of an alternative arrangement comprising thepresent invention with parts of the structure broken away to illustrateportions in transverse section.

In Fig. 1 of the drawings,'the trainer will be seen to comprise a seatIll before which is. located an airplane type control stick I2 andrudder pedals I4. Fore and aft movement of the control stick moves acontrol cable I6 which passes around pulleys I8 and into a box-likehousing 20 located some distance forwardly of the controls I2 and I4.Side to side movement of the control stick I2 rotates a shaft 22, thuscausing ro- 'tation of a crank arm 24 secured thereto to which isattached ,a second control cable 26 lead- .ing into the box-like housing2li. The rudder pedals I4 are secured to a rudder bar 28 pivoted about avertically extendingpin 30. This rudder bar is connected at one side ofits pivot point to` a third control cable 32 which also leads into thebox-like housing 20.

From the above it will be seen that movement of the controls I2 and I4moves the three cables I6; 26 and 32, and that these three cables leadlythis sphere is illuminated by several incandescent lamps 36 locatedwithin a ring type reflector 3a, and this ring of lamps surrounds'a lens4i! bymeans of which the upper illuminated portion of the sphere 34 isprojected upon a screen 42 after being reflected by a mirror 44. Thescreen 42 is of the translucent type and is located in front of theoperator in such a position that it appears to the operator that he isviewing the scene through the wind screen of an airplane.

The housing 2li,` as is fully explained in th previously mentionedpatent, No. 2,336,436, contains mechanism for rotating the sphere 34 inany direction at any speed under the influence of the movement of thecontrol cables I6, 216 and 32. Thus the portion of the sphere locatedimmediatelyv beneath the lens 4U is constantly changing unless theairplane controls are in neutral position and the operator thereforeobtains the impression that the attitude of the airplane is constantlychanging.

As an example, moving the stick I2 rearwardly will cause the sphere 34to rotate about a transverse axis so as to `cause the earth portion torecede downwardly from the view upon the screen 42, and a greaterportion of the sky area of the sphere to appear upon the screen 42.Similarly, movement of the stick I2 from side to side will cause thesphere 34 to rotate about a vertical axis, thus causing the view uponthe screen 42 to be tilted from side to side, while movement of therudde'r pedals I4 causes the sphere 34 to rotate about a longitudinalaxis, thus causing the view to move across the screen 42 from side toside. The above described mechanism in general comprises the subjectmatter of the previousf ly mentioned patent and needs no furtherdescription here, inasmuch as description in greater detail would notserve to illuminate the present invention.

In the present invention the box-like housing 20 is mounted upon theupper end of an internally threaded tube 46 and is guided for verticalmovement by members 41. The threaded tube 46 is fitted to a threadedshaft 4B which is driven through a slip type clutch 50 from a gearreduction box 60. The housing 20 therefore rests upon the gear box 60and will be raised or lowered, depending upon the direction ot rotationof the shaft 48. The gear box receives its power from a small reversingmotor 42. Thus the 'direction of rotation of the shaft of the motor 42and the speed of rotation of this shaft will determine the direction ofvertical movement of the housing and the speed at which this movementtakes place.

The vertical movement of the housing 20 is limited between upper andlower stops 64 and 68, respectively, which are mounted upon a stationaryframe member 6l. Between these limit stops, the movement of the housingis free and isdirectly under the influence of the motor 62. When thehousing impinges against either the upper stop 64 or the lower stop 46,the clutch i0 will slip, thus permitting the motor to run without movingthe housing 20.

Inasmuch as the sphere I4 is supported within and moves with the housing24, vertical movement of the housing will shorten and lengthen theoptical distance between the upper surface of the sphere 34 and thescreen 42. Downward movement of the sphere 34 will therefore decreasethe size of the image upon the screen 42, while upward movement of thesphere 34 will increase the size of this image.

'I'he range of movement of the sphere I4 upwardly and downwardlynormally would cause the sphere to move in and out of focus. For thisreason the lens 42 is mounted in a slidable lens tube 10 having a socket12 in one side which embraces a ball I4 secured at the end of a bellcrank I6 pivoted at its mid point to a bracket 18 attached to thestationary member DI. 'Ihis bell crank extends radially outwardly fromthe socket 62 to its pivot point and thence downwardly and at its lowerend is provided with a roller I0 which rides upon the surface of a cam'Ihe cam is formed upon the edge of a member which extends verticallyand is secured to the movable housing 2l. 'Ihe lower portion of this camextends outwardly agreater distance away from a line drawn verticallythrough the sphere 1l drum 84 and shaft 8S.

34, than does the upper portion of this cam. Between its upper and lowerportions the cam track sweeps downwardly and outwardly as may best beseen in Fig. 1. Thus, upward movement of the sphere 34 and housing 20will cause the cam track I2 to push the roller 80 outwardly. This causesthe opposite end of the bell crank 'Ii to be moved downwardly, therebymoving the lens tube downwardly. It will be seen, therefore, that upwardmovement of the sphere 34 causes the lens 40, to be moved a greateroptical distance from the screen 42, while downward movement of thesphere 34 causes the lens 40 to approach the screen 42. The particularcam proille should be shaped for the particular lens 40 used. It shouldbe such, however, that the lens 4U is always kept in focus.

The control cable I6 from the lower end of the stick I2 passes around adrum 84 attached to a control shaft B6 leading into a control box 84, sothat movement of the control stick I2 backwardly and forwardly willcause rotation of the 'I'he mechanism within the control box 88 isillustrated diagrammatically in Fig. 2 in which the shaft BS is shown ascarrying a rheostat arm 90 and a forked toggle switch tripping arm 92.The rheostat arm 90 when in the straight-up position shown in Fig. 2does not make contact with any electrical member. When the shaft isrotated in either direction, however, the outer end of the rheostat armis brought into contact with a series of rheostat buttons 94 which arearranged in opposite pairs, the two buttons in each pair being connectedtogether and arranged on` alternate sides of the vertical position.'I'he uppermost pair of these buttons is connected to the highresistance end of a resistance element 98, while progressivelydownwardly arranged pairs of buttons are connected to progressivelylower resistance taps, the opposite end of the resistance element beingconnected to the lowermost buttons and to one side of an electricalenergy source circuit, indicated by the binding Post I8.

It will be seen, therefore, that rotation of the rheostat arm in eitherdirection away from the vertical will rst complete an electrical circuit:between the binding post 98 and a line I00 connected to the rheostatarm 90. At the time this contact is made the resistance in the circuitwill be at a maximum. As the arm 90 moves progressively downwardly ineither direction, resistance will be progressively removed from thecircuit until when the lowermost buttons are reached, the resistanceunit 96 will be entirely cut out of the circuit established through therheostat. Further, it will be seen that since movement of the shaft 86is brought about by movement of the stick I2, slight forward movement ofthe stick I2 will pull on the cable IGjthus causing the drum 84 and theshaft 88 to rotate in a clockwise direction, thus making contact withthe first button to the right of the arm 90, thereby completing a highresistance circuit through the rheostat. Likewise, backward movement ofthe stick I2 will cause rotation of the shaft 86 in the oppositedirection, thereby establishing high or low resistance connections withthe buttons to the left of the arm Il, depending upon the degree ofmovement of the stick. i

The rheostat comprised of the arm 90, buttons 94 and resistance elementI6 is connected in series with the reversing motor 62. 'I'he motor istheground.

3l is rotated about its transverse axis in such,

climbing attitude,

shown ascomprised of a ileld elanent il! and anarmature"Landisconnectedhymeans of' toggle trip arm 92 where it will be seenthat the toggle lever indicated by the numeral lll extends upwardly intoa position within the yoke H2 of the toggle trip arm 92. Initialrotational movement of the shaft 8S in one direction therefore willtrip. the double pole, double throw toggle switch HIB in one direction,while initial movement of the shaft 86 in the oppositedirection willtrip the toggle switch IBG in the opposite direction. Since thereversing motor 82 is connected through this reversing toggle switch, itwill be seen that the direction of initial movement of the shaft I6 willdetermine' which direction the motor 62 will run. That is, slightbackward movement of the stick i2 will trip the toggle switch lili inone direction and this switch is so connected to the motnr 62 thatinitial rotation of the motorwillbeinsuch adirection as tocause thesphere 3l and housing 20 to be lowered. Movement of the stick in aforwardly direction likewise will trip the toggle switch |06 in theopposite dlrection, thus establishing a circuit for rotating the motor$2 in the proper to raise the -sphere Il.

aAssumingthatthe contmlstlckisintheneuhal position, the device opemtesin the following manner: The neutral location of the stick causes thearm Sl to take the verticalposition shown in Fig. 2. Thus the -motorisnot energized and no vertical movement of the sphere 34 takes placeThe view seen'upon the screen l2 therefore remains constant as to size.Now if under these conditions the operator wishes to simulate a dive,the stick l2 is moved forwardly. This trips the toggle switch N8 andmoves the rheostat arm I0, thus establishing a circuit through the motor62. The circuit as thus established is initially of high resistance. Themotor 62 therefore runs slowly, thus causing the sphere 34 slowly to ap--proach the screen 42, thereby giving the impression that the operatoris gradually approaching Simultaneously, of course, the sphere directionthat the horizon line is raised toward the top of the screen, thusgiving the illusion that the'plane is in a gliding attitude. Furtherforward movement of the stick increases the speed at which the spherelis raised, thus giving the impression that the ground is being morerapidly approached, while simultaneously the horizon line is morerapidly moved upwardly.

ment oi the image such as would be' caused by moving the nose o! anairplane downwardly.

l If at any time by maneuvering the controls.4

the housing .2l is brought against either of the stops Il, it willremain'in'this position until the controls are moved in the oppositedirection whereupon reversal of the position of the toggle switch l willcausemovement of the housing 20 Y away from the stop against which itwas im- B-, InFig.3ofthedrawings,lhaveshowna somewhatsimpliedexpedient-for giving much the same illusion provided by thedevice above described. 'Ehe illusion is not so extensive, howy.

ever, but the arrangement illustrated in Fig. 3 is much more economicalto construct and therefore is recommended in those instances in whichthe expenditure necessaryto provide the mechanism illustrated in Egaland 2 is not instilled.

The device illustrated in F153 is comprised of a spherical envelope IIIof transparent material. This envelope may be formed of glass or atransparent plastic material constructed in any desired manner. such asby molding in halves, the halves being later cemented together. Thisenvelope is located/within the sphere rotating mechanism indicatedgenerally by the numeral 20. It may be rotated and controlled throughoperation of half I2. simulates the Sky. The Sphere lli is If the stickis moved rearwardly somewhat to check the speed of the dive, thevelocity 'of upward movement of the sphere 34 decreases, while if thestick is moved rearwardly past the neutral posltion so as to simulateplacing the trainer in the the toggle switch IM will be tripped in theother direction, thus causing the sphere to recede from the screen 42,all of these movements being correlated with proper changes in the viewupon the screen. For instance, placing the airplane controls in a divingattitude not only increases the size of the image, thus giving theimpression that the operator is moving toward the earth, but it alsocauses a displace- Av"located within the envelope III in an oli centerposition with the earth simulating portion il! much-closer to theenvelope than the skysimulating portion In. It is sewred in place bymeans of a plurality of posts |22 extending from the inner sphere to theenvelope. If the inner sphere lli is of v'sumcient weight to noticeablyaect the balance of the assembled sphere. the device can be balanced bymeans of counterweights located within the inner sphere.

The operation of this device is as follows: Whenever the controls areoperated so as to place the aircraft in a diving or gliding attitude.the spheres will rotate so as to cause the horizon line to move upwardlyupon the screen l2, thus bringing a larger portion of the earthsimulating area of the sphere lli into view. The longer the controls areheld in Ithis position, the straighter downwardly the airplane willappear to be pointed toward the earth, .and since the sphere H6 ismounted oi center. the effect will be to Acause a noticeable approach ofthe sphere toward the scree'n 42, that is, a shortening of the opticaldistance between these two elements. Therefore, whenever the operatorplaces the aircraft in a diving attitude, the earth will appear toapproach the operator. Conversely, when the nose of the airplane iselevated, the earth portion will appear to recede both from the operatorand also downwardly on the screen I2.

Another feature of the device shown in Fig. 3 is of the sphere iii isformed in relief. That is, trees, bulldings, mountains and other earthformations are displayed in relief upon the globe rather than beingmerely painted thereo This gives the operator a third dimensional eiectwhich enhances the naturalness of the simulated view. It win beappreciated that when desired. the apparatus shown in Figs. l and 2 maybe used together with a sphere comprisedof antransparent envelope lilenclosing an earth and sky simulating sphere with the earth portionshown in relief, and in which the circumscribed sphere is centrallylocated within the envelope. In this case the outer envelope providesmerely a smooth surface better'adapted for operation with the mechanlsmlocated within the'housing 20, since as will be readily appreciated. theillustration of landmarks in relief upon the sphere H6 will necessarilyproduce a rough surfaced sphere, which is not well adapted to be drivenby the mechanism in the housing 2l unless enclosed within a smoothenvelope of the type shown.

While I have shown and described a' particular embodiment of myinvention, it will be apparent to those skilled in the art that numerousmodi ncations and variations may be made therein without departing fromthe underlying principles of the invention.4

I claim:

l. In a pilot training device of the type in which movement of airplanecontrols produces movement of a scene projected. upon a screen in such amanner that changes in the projected stone simulate changes ln attitudeo f the sirplane, means to produce relative approaching and recedingmovement between the scene and the screen so as to shorten and lengthenthe optical and to lengthen said optical distance when saidairplanecontrols are moved in an opposite manner.

2. In a pilottraining device of the type in which movement of airplanecontrols produces movement of a scene projected upon a screen in such amanner that changes in the projected scene simulate changes in -attitudeof the airplane. means to produce relative approaching and recedingmovement between the scene and the screen so as to shorten and lengthenthe optical distance between these members, power driven means toproduce said movement, means operated by the airplane controls to causesaid power driven means to shorten the optical distance between thescene and the screen when the airplane controls are moved as though toplace the simulated aircraft in a diving attitude and to lengthen saidoptical distance when said airplane controls are moved in an oppositemanner, a movable projection lens arranged between the scene and thescreen to project an image of the former upon the latter, and means tochange the position of said lens simultaneously with changes in theoptical distancebetween the scene and the screen so that said scene isalways kept in substantial focus upon said screen.

3. In a pilot training device, a rotatable sphere having earth and skysimulated portions thereon. means to rotate said sphere, means tocontrol the rotation of said sphere, the last said means including a setof airplane controls, a projection screen, optical means to project animage of a.

controls for causing said power driven means to move said sphere-towardsaidscreen when the l airplane controls are moved as though to place thesimulated aircraitin a diving attitude.

4..' In a pilot training device. o rotatable sphere having earth and slwsimulated portions thereon.' means to rotate said sphere. means tocontrol tuo rotation of said sphere the last said 5 means including aset of airplane controls. a projection-screemopticalmeans to project animage of a portion of the suriaceof said sphere on said screen, meansmounting said sphere for movement toward and vaway from said screen soasto shorten and 'lengthen' the optical distance 4between thesemembers.' power driven means for moving said sphere toward and away romsaid screen, control means operated by said airplane controls forcausing said power driven means to move said sphere toward said screenwhen the airplane controls are moved as though to place the simulatedaircraft in a divingattitude, and

control means operated by said airplane controls tween the scene and thescreen so as to shorten and lengthen the optical distance between thesemembers. Power driven means to produce said movement. means operated bythe airplane controls to cause said power driven means to shorten theoptical distance between the scene and the screen when the airplanecontrols are moved as though to place the simulated aircraft in a divingattitude and to length said optical distance when said airplane controlsare moved in an opposite manner, and means operated by said power drivenmeans for moving said optical means so as to keep said view upon thescreen in substantial iocus as said sphere from said scene.

6. In an airplanetrainer, a set of airplane controls, a rotatablesphere, said sphere having sky and earth simulating portions thereon,means to A-rotate said sphere, means operated by said airshorten andlengthen the optical distance between these members, power driven meansfor moving said sphere toward and away from said plane controls fordetermining the direction and velocity of rotation of said sphere, aprojection screen, optical means for projecting a portion of the surfaceof said sphere upon said projection screen. and means for causing theview upon said screen to become enlarged when said airplane controls aremoved as though to pui-the simulated aircraft into a diving attitude.the last said means comprising a substantially transparent spherecircumscribing the first said sphere, said spheres being arranged ineccentric relation to each other with the earth simulating portion ofthe inner sphere arranged closer to the surface of the outer sphere thanthe sky simulating portion thereof, and means to support said innersphere in substantially iixed relation sphere.

'7. In an airplane trainer, a set of airplaneoontrols, a rotatablesphere, said sphere having sky and earth simulating portions thereon*means to rotate said sphere. means operated by said airplane controlsfor determining the direction and to said outer moves toward and awayvelocity of rotation of said sphere, a projectionscreen1 optical meansfor projecting a portion of the surface of said sphere upon saidprojection screen, and means for causingthe view upon said A' screen tobecome enlarged when said airplane controls are moved so as to put thesimulated aircraft into a diving attitude. the last said meanscomprising a suixitantially transparent sphere circumscribing the iirstsaid sphere, said spheres being arranged in eccentric relation to eachother with the earth simulating portion of the inner sphere arrangedcloser to the surface of the outer sphere than the sky simulatingportion thereof. means to support said inner sphere in substantiallyiixed relation to said outer sphere, and at least'the earth simulatingportion of said inner sphere being formed in relief.

8. In a training device, a spherical scene element adapted to be rotatedabout any axis in a. cradle comprising a smooth transparent sphere forengagement with the supporting and rotating mechanism. an opaque spherelocated within said transparent sphere, said opaque sphere having sb andearth simulating portions formed thereon,andmeansxingtheinnersphereinsubstantially immovable relation to the outer sphere.

9. The combination called for in claim 8 in which the earth simulatingportion of said inner Sphereis locatedclosertothesurfaceoftheoutersphere than the skysimulating portion of said inner sphere.

l0. The combination called for in olaim-8 in which the earth simulatingportion ol' said inner `sphereislocatedclosertothesurfaceofifheoutersphere than the sky simulating portion ofsaid '1a. In a. puoi miningdevise-of the type in which movement of airplane controls produces-movementofasceneproiectednponascreenin such a manner that changes inthe proiected scene simulate-a view seen during similar changes inattitude of an airplane, reversing motor means to produce relativeapproaching and receding movement between the scene and the screen so asto shorten and lengthen the optical distancebetweenthesemembers,arevexsingswitchcir' cuit toidetermine the directionof said movement, means operated by the airplane controlstoshiit saidreversing switch circuit sons to shortenthe which at least the earthsimulating portion of 4 0 4 said inner sphere is formed in relief.

12.1napilottrainlngdeviceofthetypein which movement of airplane controlsproduces movement of a scene 'projected upon a screen in such a mannerthat changes in the projected scene simulate the view seen duringsimilar changes in attitude of an airplane, reversing motor means toproduce relative approaching and receding movement between the scene andthe screen so as to shorten and lengthen the distance between thesemembers, a reversing scene and the screen when the airplane controls aremoved as thoughto place the aircraft in a diving attitude and tolengthen said optical dis tance when said airplane controls are moved inan opposltemanneropticaldistancebetweenthesceneandthescreen when theairplane controls aremovedasthoughtoplacetheaircraftinadivmgattitudeandto lengthen said-optical distancewhen said airplane controlsaremovedinanoppositemannenmotor speed controlmeans, and means to achiate the last said means to increase the motorspeed as the controls are moved-as though to'place the simulatedairplane in a more steeply climbing or divingattihlde.

14.1n a pilot training devlce.. a rotatable spherehavingearthandskysimulated portions thexeongmeansmrotatesaidspherameanstoccntroltlierotationotsaidspherathelastsaidmeansincludlngasetotairplanecontrolaaxnojectionscxmoptioalmeanstopmiectanimeofaportignofthesurfaceotsaidsphereonsaidsmemmeansmnuntingsaidsmeretormovenienttowardaud'zwrayfromsaidscreensoastomovementofascene Proiecteduponascreenin suchamannerthatchangesintheprojected scene simulate a view seen during similar changes in attitudecian airplane, meanstoproducerelative approaching and receding movementbetween the scene and the screen so as to shorten and lengthen theoptical distance between these members, means to produce said movement,and means operated by the airplane controls to cause the last said meansto shorten the optical distance between the scene and the screen whenthe airplane controls are moved as though toplace the .simulatedaircraft in a diving attitude, and to lengthen said optical distancewhen said airplane controls are moved in an opposite manner.

cnmncmn' oF bol-inlichten. A

l* ,WILLIAM H. Emmen."

:mi- 1g reby'ertifid that 4ai-mn?l appears in the printed specificationbf-thafb'vemunhered patent'requiring correctionas follows: Pag' A5 first6,1 "I, fqr the wodafspis tp" read-#as thmxgh toe-; l @mumugqsgianettgrs Pian-.erm ahquldbe Ninth -this" correction there? that 'smemay' conformot tha 4:"eaooi'c lofthe calseir; the Patent 0f- .18e-a1) l'l Acting 'Commissioner' of Patents.

